This invention relates to integration means, and more particularly to a device added to the upper receiver of a firearm for incorporating firearm ancillary equipment.
As the field of combat weaponry expands, numerous add-on enhancements have become available for attachment to standard firearms thereby significantly upgrading the capability of the firearm. However, because of the variety of shapes of the upper receivers of different firearms, the add on enhancements must be modified each time they are sold for a different firearm. This also results in high cost for the add-on enhancements.
The Swan/Weaver rail described in U.S. Pat. No. 4,845,871, incorporated herein by reference and hereinafter referred to as '871, addresses a portion of this problem. The female portion of said rail is a quick detachable interface means for modular enhancements. However, the said rail requires a first rail (weaver rail) to be attached to the firearm, typically to the arced handle on the U.S. Army M16 combat firearm, and different means on other types. The first rail must be designed for each firearm to accommodate the differences between firearm receivers. Since the male portion of the Swan/Weaver rail is easily removed by the firearm operator, they are also easily lost and calibration and weapon sighting are difficult and nonuniform.